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Re: Clause 51 (XSBI) questions

Hi Justin,

Would it not make more sense to specify the timing requirement,
both at the PMA and the PCS?  I can envisage a situation where
a vendor selling PCS+PMA modules buys PCS devices from one
vendor and PMA devices from another vendor.  The PCS vendor
and the PMA vendor would have to have prior knowledge of the
board design, which may or may not be possible.  Specifying
timing requirement for both devices allows easier inter-working
in my opinion.

Erik Trounce

In message "Clause 51 (XSBI) questions", Jscquake@xxxxxxx writes:
>3 & 4) timing for input and output (PMA & PCS)
>    As was stated by Henning, the XSBI targetted to only spec the
>    PMA input (transmit direction) and the PCS input (receive
>    is not a direct translation from OIF (SFI-4). Most notably is the 
>    non-inversion of the clock from the PMA to the PCS. 
>    While this "helps" the systems vendor to not have to do an
inversion on
>    the board. It does make it inconsistent with the transmit side,i.e.
>    latched in on the rising edge of the clock. The transmit side,
>    OIF would still warrant the system vendor to do an inversion on the
>    I don't have a strong position on this but I think it would be
>    try and have a consistent edge for both transmit and receive.